Geochemical characteristics and tectonic interpretation of garnet mica schists of Patharkhola area in Kumaun Lesser Himalaya, Uttarakhand Himalaya, India

Abstract

The Patharkhola area is exposed in the core of the southern limb of the Dudhatoli syncline in the Kumaun Lesser Himalaya. Garnet mica schists of the Patharkhola occur in the folded outcrop pattern being located in between the limbs. They are dominantly composed of garnet, biotite, muscovite, chlorite, plagioclase and a subordinate amount of quartz. Garnet, both xenoblastic as well as idioblastic, is wrapped round by phyllosilicates minerals. These investigated rocks exhibits slightly LREE depleted patterns (LaN/SmN = 0.7, LaN/YbN = 0.64) with flat HREE patterns (SmN/YbN = 0.89). Field evidence along with geochemical characteristics suggests that the Patharkhola schists are peraluminous in nature, showing sedimentary sources having silt to silty clay protolith. They were formed in active continental margins in arc-type setting where the sediments were received both from arc and continental crust.